Answer:
4.06 Hz
Explanation:
For simple harmonic motion, frequency is given by
where k is spring constant and m is the mass of the object.
Substituting 0.2 Kg for mass and 130 N/m for k then
![f=\frac {1}{2\pi}\times \sqrt{\frac {130}{0.2}}=4.057670803\\f\approx 4.06 Hz](https://tex.z-dn.net/?f=f%3D%5Cfrac%20%7B1%7D%7B2%5Cpi%7D%5Ctimes%20%5Csqrt%7B%5Cfrac%20%7B130%7D%7B0.2%7D%7D%3D4.057670803%5C%5Cf%5Capprox%204.06%20Hz)
Answer:
a = 3 m/s^2
Explanation:
Vi = 10 m/s
Vf = 40 m/s
t = 10 s
Plug those values into the following equation:
Vf = Vi + at
40 = 10 + 10a
---> a = 3 m/s^2
Mechanical energy E = mgh + 1/2mv²
When he starts, let h = 0 ⇒ E₁ = 1/2mv₁²
When he reaches height h ⇒ E₂ = mgh + 1/2mv₂²
Without friction, energy is conserved at all times.
E₁ = E₂
↓
1/2mv₁² = mgh + 1/2mv₂²
↓
1/2v₁² = gh + 1/2v₂²
↓
gh = 1/2(v₁² - v₂²)
↓
h = (v₁² - v₂²) / (2g)
The speed of the ball just before impact was v=√(2gh) = 6.26m/s. The acceleration is twice this over the time (twice because the second speed is the same in the other direction, meaning the total change in speed is 2V)
a = 12.52/0.10 = 125.2m/s²
The force is F=ma, so F = 0.5kg·125.2m/s² = 62.6N